Autohelm Display & Raymarine SmartPilot Computer Issue

[Quig]

My 4788 Autopilot consists of:
Raymarine SmartPilot course computer, fluxgate compass and hydraulic servo steering. The operator control LCD display is an Autohelm ST7001 (main station) and ST7000 flybridge station. This system was on the boat when I bought it a few years ago – looks like all components were probably Raymarine to start with and the operator display might have gotten changed out at some point with the Autohelm panels. The chart plotter - Sitex Explorer II plus was never connected to the AP.
The system works fine in AUTO mode – point the boat on a heading, hit AUTO on the Autohelm and the boat stays exactly on the line.
I recently connected my chart plotter NMEA 0183 output to the navigation system input on the Autohelm and, while it does appear to be working, it’s not completely right:

• I place a waypoint on the chart plotter and initiate a GOTO – straight line is plotted from vessel position to the WP.
• Place the Autohelm in AUTO and hit TRACK
• The boat follows the course line with WIDE meanderings to both sides of the line returning to and crossing over the course line VERY slowly.
• When the boat reaches the WP, there is no “ARRIVAL” alarm and continues on the heading past the WP with the indicated bearing on the Autohelm now reversed (180 degrees) and the “DISTANCE TO WP” increasing.

This looks like it just needs some tuning or calibration – and possibly a setting of ARRIVAL ALARM or something. The problem is when I try to enter the calibration mode on the Autohelm and scroll through the menu, the menu items does not match the menus in the Autohelm manual – and nor does it match the calibration menus on the Raymarine SmartPilot.
Has anyone encountered a problem like this and can anyone suggest some troubleshooting or adjustments I could make? I recorded the existing settings and calibration data if anyone is interested in helping me assess if there is some parameter that might be out of whack!?! As I said, the functionality is there and seems to be working but just a couple of glitches. Since this seems to be a “hybrid” autopilot system, does anyone have any suggestions please?
Thanks in advance for any help!
Leo

[Quig]

UPDATE: Problem solved...almost!

(Corrections to my earlier post: Pilothouse Autohelm is a ST7000 and Flybridge is a ST6000)

I had puzzled over why it was that the Autopilot performed nearly flawlessly at course keeping in AUTO mode but not in TRACK mode! In reviewing all the literature I have, it seemed like the only option open to me was adjusting the settings of the control algorithm in the Autopilot (Ruder Gain, Rate, etc.). But this didn't make sense since the control parameters worked perfectly in AUTO and in TRACK mode, the same parameters would be used in the control program. It had to be associated with the Chart Plotter-Autopilot interface.

In eliminating possible causes, I discovered an error in the connections of the NMEA 0183 data output from the Chart Plotter to the Autopilot (this occurred because I had been working from the wrong manual (there was no manual onboard and I could not find the correct one online so I downloaded one that was a close approximation - still not the exact one!). Corrected that and headed out for sea trials - performance was not appreciably better. Next step in my troubleshooting process of elimination was to review the data output from the Chart Plotter - I had noted in looking at the NMEA 0183 Data Table In the Sitex Explorer Plus that several of the output words in the NMEA sentences were turned OFF (don't know why???) so I decided to try turning all of these ON and "voila" - quite good course tracking performance! The boat turns at waypoints onto the course to the next waypoint as would be expected.

The only remaining issue is that at waypoints on the route where the course correction is a very large angle, the Autopilot cannot pick up the new course to the next waypoint before ringing in an "OFF COURSE" alarm. I think this is probably just a matter of setting up the tolerance for course changes or possibly relaxing the alarm parameters a bit!

Hope this might be helpful or at least interesting to some readers!

Cheers
Leo